ASTextKitFontSizeAdjuster.h

//
//  ASTextKitFontSizeAdjuster.h
//  Texture
//
//  Copyright (c) 2014-present, Facebook, Inc.  All rights reserved.
//  This source code is licensed under the BSD-style license found in the
//  LICENSE file in the /ASDK-Licenses directory of this source tree. An additional
//  grant of patent rights can be found in the PATENTS file in the same directory.
//
//  Modifications to this file made after 4/13/2017 are: Copyright (c) 2017-present,
//  Pinterest, Inc.  Licensed under the Apache License, Version 2.0 (the "License");
//  you may not use this file except in compliance with the License.
//  You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//

#import <UIKit/UIKit.h>
#import <AsyncDisplayKit/ASTextKitAttributes.h>
#import <AsyncDisplayKit/ASBaseDefines.h>

NS_ASSUME_NONNULL_BEGIN

@class ASTextKitContext;

AS_SUBCLASSING_RESTRICTED
@interface ASTextKitFontSizeAdjuster : NSObject

@property (nonatomic, assign) CGSize constrainedSize;

/**
 *  Creates a class that will return a scale factor the will make a string fit inside the constrained size.
 *
 *  "Fitting" means that both the longest word in the string will fit without breaking in the constrained
 *  size's width AND that the entire string will try to fit within attribute's maximumLineCount. The amount
 *  that the string will scale is based upon the attribute's pointSizeScaleFactors. If the string cannot fit
 *  in the given width/number of lines, the smallest scale factor will be returned.
 *
 *  @param context                 The text kit context
 *  @param constrainedSize         The constrained size to render into
 *  @param textComponentAttributes The renderer's text attributes
 */
- (instancetype)initWithContext:(ASTextKitContext *)context
                constrainedSize:(CGSize)constrainedSize
              textKitAttributes:(const ASTextKitAttributes &)textComponentAttributes;

/**
 *  Returns the best fit scale factor for the text
 */
- (CGFloat)scaleFactor;

/**
 *  Takes all of the attributed string attributes dealing with size (font size, line spacing, kerning, etc) and
 *  scales them by the scaleFactor. I wouldn't be surprised if I missed some in here.
 */
+ (void)adjustFontSizeForAttributeString:(NSMutableAttributedString *)attrString withScaleFactor:(CGFloat)scaleFactor;

@end

NS_ASSUME_NONNULL_END